Left Booster Recovery To Serve As Test

CAPE CANAVERAL — Salvage crews will try to retrieve a large piece of Challenger's left booster rocket from the ocean floor today in an important test of recovery techniques.

The 4,200-pound booster casing is 210 feet below the surface about 25 miles off the Cape.

The segment, which is over 7 feet long and nearly 4 feet in diameter, comes from the lower part of the booster where it was attached to the shuttle's external fuel tank.

NASA spokesman Jim Mizell said the recovery is a test of whether the same method can be used to haul up wreckage of the suspect right booster without damaging possible key evidence.

The ship Stena Workhorse, which has cranes that can lift 100-ton loads, will lower the robot submarine Gemini down to the wreckage. The sub will then use its manipulator arms to try to fasten two U-shaped rings to the booster segment.

If successful, the sub will attach a cable to the rings so the wreckage can be pulled to the surface.

Failure of the test could further delay recovery of right booster parts, which are in 1,200 feet of water about 40 miles offshore. The booster is the chief suspect in the explosion because a plume of flame shot from its side after liftoff.